The turning point came last week, when the elected prime minister of Greece was marched into an office and dressed down by the leaders of a foreign state. His plans for a referendum of the Greek people were scrapped. European Commission president Jose Manuel Barroso said he expected a government of national unity – one without any mandate whatsoever – to be installed with all the off-hand arrogance of an emperor. And so it came to pass, with Loukas Papademos, one of those technocrats which the androids in Brussels consider reliable, primed to take over the top job.

The left must abandon the EU. For anyone to still be defending this type of behaviour is embarrassing and contemptible. Until the left accepts the complete failure of the project, it cannot contribute to the debate on the future of Europe. That leaves us without a humane or compassionate assessment of our predicament, rather than the slavish devotion to the market and dewy-eyed sentimentality about the nation state which transfixes conservative eurosceptics.

The Greek people did not behave in a manner which is in any way different to their British counterparts. There was more borrowing than earning, as there was here. They were subject to the sudden collapse of the western financial model, as we were here. And yet their punishment is a decade of austerity, the very real prospect of people starving. Already a sub-class is being created on the streets of major cities, the homeless mingling with mental patients from institutions which can no longer afford to house them. Families which refuse to pay astonishing tax increases – mainly because they cannot afford to – are being threatened with having their electricity supply cut off.

This is too high a price. The left's support for the EU relies on a variety of arguments, including an association with internationalism, a power-base to counteract US influence in foreign affairs, the source of more progressive penal and employment laws than in the UK and as a vehicle for ensuring peace in Europe. Even if all these arguments held true, the sacrifice would not be worth it. The complete collapse of democratic legitimacy in Europe is not a price we could possibly be willing to pay. But it doesn't matter, because the arguments do not hold true.

Internationalism is damaged, not aided, by the EU. It has created enormous domestic anger and humiliation. It overlooks the fact that European people primarily view their community in a national and linguistic context. Few people complain, for instance, when money gets transferred from south to north England, but German taxpayers complain when their money goes to Greece. The distinction between financial and political union is unbearable precisely because the prospect of political union is intolerable. Anyway, the welcome parts of the EU's internationalism, such as the end of visa restrictions on the continent, could be maintained along with the common market long after we have jettisoned the more grotesque aspects of the European project.

The idea that the EU can counterbalance American influence is now so ridiculous as to be barely worth mentioning. The EU has no democratic legitimacy. Its own voters have rejected it whenever it came to a referendum, forcing its leaders to tread over their wishes or, at best, hold new elections until the right answer is reached. Its bullying, elitist nature is only counteracted by the total invisibility of its foreign policy and presidential representatives – Cathy Ashton and Herman Van Rompuy.

As for employment law, the EU has proved more pro-business than the left could ever have dreamed. This was evidenced from the start, when the European Central Bank was given power over national governments. Now those same governments are impotent in the face of the markets and a failed currency system based on aspirations about human behaviour rather than its reality. European leaders now happily countenance the prospect of people starving in Greece to salvage their disastrous, world-breaking toy.

Given this degree of injustice, it is ironic that the EU's advocates, such as Nicolas Sarkozy, claim it prevents war in Europe. Actually, trade relations between democratic states have a greater explanatory role than the EU in explaining the lack of warfare over the last half century. The enforced poverty of Greece and the supreme political arrogance of Germany and France will do more to foster discontent than the absence of a gigantic bureaucratic monstrosity. Sarkozy himself is the worst advocate for such a theory. Whether he smirks at the (admittedly pathetic) Italian premier Silvio Berlusconi, tells Brits they can't understand the "subtlety" of European political arrangements or publicly humiliates the Greek prime minister, he is a victory for small-minded xenophobia and fecklessness who true internationalists should intuitively jettison.

Unless the left abandons the EU, it cannot morally or logically contribute the debate over what is happening to this continent. The right would restrict the debate to the institution alone, claiming that the single currency is the only problem. But the same criticism of the EU must be applied to the market, something the right is incapable of doing. Just like EU leaders, the markets sacrifice people for the needs of capital.

We need an assessment which recognises that the taxpayer should not have to pay for the faults of the financial sector, that those who bought bonds knew the risks, that a system whereby losses are nationalised and profits privatised is a form of feudalism and, finally, that morality is not separate to economics. Only the left can make that assessment, but to do so it must forsake the European project.

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